A clearer error message when passing -R to regrtest.py with
release builds of Python.
diff --git a/Lib/test/regrtest.py b/Lib/test/regrtest.py
index 86961b0..314e7e1 100755
--- a/Lib/test/regrtest.py
+++ b/Lib/test/regrtest.py
@@ -513,6 +513,9 @@
     else:
         cfp = cStringIO.StringIO()
     if huntrleaks:
+        if not hasattr(sys, 'gettotalrefcount'):
+            raise Exception("Tracking reference leaks requires a debug build "
+                            "of Python")
         refrep = open(huntrleaks[2], "a")
     try:
         save_stdout = sys.stdout